A large proportion of healthy African Americans have been observed to have a white blood cell count (WBC) that is persistently lower than the normal range defined for individuals of European ancestry [1]â[5].
Energy is only released when chemical bonds are formed. In general, a chemical reaction involves two steps: 1) the original chemical bonds between the atoms are broken, and 2) new bonds are formed. These two steps are sometimes lumped into one event for simplicity, but they are really two separate events.
Exothermic and Endothermic Reactions. The release of energy in chemical reactions occurs when the reactants have higher chemical energy than the products. The chemical energy in a substance is a type of potential energy stored within the substance. This stored chemical potential energy is the heat content or enthalpy of the substance.